US7134852B1 - Seal member for vortex compressor - Google Patents

Seal member for vortex compressor Download PDF

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Publication number
US7134852B1
US7134852B1 US11/333,369 US33336906A US7134852B1 US 7134852 B1 US7134852 B1 US 7134852B1 US 33336906 A US33336906 A US 33336906A US 7134852 B1 US7134852 B1 US 7134852B1
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United States
Prior art keywords
vortex
stationary
rotatable
groove
seal member
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Expired - Fee Related
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US11/333,369
Inventor
Chin-Liang Lai
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Heng Sheng Precision Tech Co Ltd
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Heng Sheng Precision Tech Co Ltd
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Priority to US11/333,369 priority Critical patent/US7134852B1/en
Assigned to HE JHANG ENVIRONMENTAL TECHNOLOGY CO., LTD. reassignment HE JHANG ENVIRONMENTAL TECHNOLOGY CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: LAI, CHIN-LIANG
Assigned to HOLIN ELECTRIC LTD. reassignment HOLIN ELECTRIC LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HE JHANG ENVIRONMENTAL TECHNOLOGY CO., LTD.
Assigned to HENG SHENG PRECISION TECH. CO., LTD. reassignment HENG SHENG PRECISION TECH. CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HOLIN ELECTRIC LTD.
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/02—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
    • F04C18/0207—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form
    • F04C18/0215—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form where only one member is moving
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C27/00—Sealing arrangements in rotary-piston pumps specially adapted for elastic fluids
    • F04C27/005—Axial sealings for working fluid

Definitions

  • the present invention relates to a seal member installed in the end surface of each of the stationary vortex body and rotatable vortex body.
  • a conventional vortex compressor includes a casing in which a compression chamber and an expelling chamber are defined and separated by a stationary vortex body.
  • the refrigerant is introduced into the compression chamber via an inlet and the rotatable vortex body is rotated relative to the stationary vortex body to compress the refrigerant.
  • the pressure between the base board and vortex surface of the stationary vortex body and the rotatable vortex body suddenly increases such that leakage might happen in axial direction. The leakage is worse when the vortex surface is worn out. This results in less efficiency for the refrigerant in the whole air-conditioning system.
  • a vortex groove 81 is defined in the end surface 8 of the stationary and rotatable vortex bodies and a seal member 9 is engaged with the groove 81 so as to improved the leakage described in the above-mentioned air-conditioning system.
  • the present invention intends to provide a seal member which includes a stepped surface defined in the first end thereof so that when the compressor is activated, the refrigerant enters the gap between the seals and the grooves to push the seal members toward the vortex boards so that the pressure is maintained. By this way, the efficiency for the compressor can be increased.
  • the present invention relates to a vortex compressor which comprises a casing in which a stationary vortex body and a rotatable vortex body are located so as to define a compression chamber and an expelling chamber with the stationary vortex body located between the two chambers.
  • the stationary vortex body and the rotatable vortex body are located in the compression chamber.
  • Each of the stationary vortex body and the rotatable vortex body has a base board and a vortex portion extends from the base board.
  • a vortex groove is defined in an end surface of each of the vortex portion and a seal member is engaged with the vortex groove.
  • the vortex groove includes a start end which is located close to the base board.
  • Each of the seal members includes a cut-off portion defined in a distal end thereof and located close to the start end of the vortex groove.
  • the cut-off portion faces an inside of the vortex groove. The refrigerant enters the gap between the cut-off portion of the seals and the grooves to push the seal members toward the vortex boards when the compressor is activated.
  • FIG. 1 is a cross sectional view of the compressor
  • FIG. 2 is a cross sectional view along line 2 — 2 in FIG. 1 ;
  • FIG. 3 shows the seal member engaged with the vortex groove
  • FIG. 4 shows refrigerant enters the gap between the seal member and the inside of the vortex groove
  • FIG. 5 shows the base board, the vortex portion, and the seal member engaged with the vortex groove
  • FIG. 6 shows a second embodiment of the seal member
  • FIG. 7 shows a third embodiment of the seal member
  • FIG. 8 is a conventional seal member and the vortex groove of the vortex body.
  • the vortex compressor of the present invention comprises a casing 1 in which a stationary vortex body 2 and a rotatable vortex body 3 are located.
  • the rotatable vortex body 3 is rotatable relative to the stationary vortex body 2 .
  • a compression chamber 4 and an expelling chamber 5 are defined in the casing 1 and separated by the stationary vortex body 2 .
  • the stationary vortex body 2 and the rotatable vortex body 3 are located in the compression chamber 4 .
  • Each of the stationary vortex body 2 and the rotatable vortex body 3 has a base board 21 / 31 and a vortex portion 22 / 32 extends from the base board 21 / 31 .
  • a vortex groove 23 / 33 is defined in an end surface of each of the vortex portion 22 / 32 .
  • a seal member 6 / 7 is engaged with the vortex groove 23 / 33 .
  • the vortex groove 23 / 33 includes a start end 24 / 34 which is located close to the base board 21 / 31 .
  • Each of the seal members 6 / 7 includes a cut-off portion defined in a distal end 61 / 71 thereof which is located close to the start end 24 / 34 of the vortex groove 23 / 33 .
  • a gap 25 / 35 is defined between the distal end 61 / 71 of the seal member 6 / 7 and the start end 24 / 34 of the vortex groove 23 / 33 as shown in FIGS. 3 and 4 and a stepped surface 62 / 72 is defined in the cut-off portion and faces an inside of the vortex groove 23 / 33 .
  • the refrigerant When the compressor is activated, the refrigerant enters into the start end 24 / 34 of the vortex groove 23 / 33 due to higher pressure and applies a force to the stepped surface 62 / 72 , the distal end 61 / 71 of the seal member 6 / 7 is then lifted upward slightly and the refrigerant then enters the gap between the seal member 6 / 7 and the inside of the vortex groove 23 / 33 till the final end 231 / 331 of the vortex groove 23 / 33 .
  • the seal member 6 / 7 is pushed by the refrigerant to contact against the base board 21 / 31 so as to effectively seal the base board 21 / 31 and the vortex portion 22 / 32 .
  • the compression ratio can be maintained and even if the seal member 6 / 7 is slightly worn out, the seal member 6 / 7 still seals the gap by the refrigerant.
  • FIG. 6 discloses a second embodiment of the seal member 6 / 7 wherein the cut-off portion is an inclined surface 63 / 73 .
  • the compressor When the compressor is activated, the refrigerant enters into the start end 24 / 34 of the vortex groove 23 / 33 due to higher pressure and applies a force to the inclined surface 63 / 73 , the distal end 61 / 721 of the seal member 6 / 7 is then lifted upward slightly and the refrigerant then enters the gap between the seal member 6 / 7 and the inside of the vortex groove 23 / 33 till the final end 231 / 331 of the vortex groove 23 / 33 .
  • the seal member 6 / 7 is pushed by the refrigerant to contact against the base board 21 / 31 so as to effectively seal the base board 21 / 31 and the vortex portion 22 / 32 .
  • FIG. 7 shows a third embodiment of the seal member wherein the cut-off portion is an inclined a combination surface 64 / 74 which is composed of an inclined section 641 / 741 and a vertical section 642 / 742 .
  • the compressor When the compressor is activated, the refrigerant enters into the start end 24 / 34 of the vortex groove 23 / 33 due to higher pressure and applies a force to the combination surface 64 / 74 , the distal end 61 / 71 of the seal member 6 / 7 is then lifted upward slightly and the refrigerant then enters the gap between the seal member 6 / 7 and the inside of the vortex groove 23 / 33 till the final end 231 / 331 of the vortex groove 23 / 33 .
  • the seal member 6 / 7 is pushed by the refrigerant to contact against the base board 21 / 31 so as to effectively seal the base board 21 / 31 and the vortex portion 22 / 32 .

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Compressor (AREA)

Abstract

A vortex compressor includes a stationary vortex body and a rotatable vortex body located in the casing so as to define a compression chamber and an expelling chamber. Each of the stationary vortex body and the rotatable vortex body has a base board and a vortex portion extending from the base board. A vortex groove is defined in an end surface of each of the vortex portion and a seal member is engaged with the vortex groove. The vortex groove includes a start end which is located close to the base board. Each of the seal members includes a cut-off portion defined in a distal end thereof in the start end. When the compressor is activated, the refrigerant enters the grooves to push the seal members toward the vortex boards to maintain the pressure.

Description

FIELD OF THE INVENTION
The present invention relates to a seal member installed in the end surface of each of the stationary vortex body and rotatable vortex body.
BACKGROUND OF THE INVENTION
A conventional vortex compressor includes a casing in which a compression chamber and an expelling chamber are defined and separated by a stationary vortex body. The refrigerant is introduced into the compression chamber via an inlet and the rotatable vortex body is rotated relative to the stationary vortex body to compress the refrigerant. During compression, the pressure between the base board and vortex surface of the stationary vortex body and the rotatable vortex body suddenly increases such that leakage might happen in axial direction. The leakage is worse when the vortex surface is worn out. This results in less efficiency for the refrigerant in the whole air-conditioning system.
As shown in FIG. 8, a vortex groove 81 is defined in the end surface 8 of the stationary and rotatable vortex bodies and a seal member 9 is engaged with the groove 81 so as to improved the leakage described in the above-mentioned air-conditioning system.
The present invention intends to provide a seal member which includes a stepped surface defined in the first end thereof so that when the compressor is activated, the refrigerant enters the gap between the seals and the grooves to push the seal members toward the vortex boards so that the pressure is maintained. By this way, the efficiency for the compressor can be increased.
SUMMARY OF THE INVENTION
The present invention relates to a vortex compressor which comprises a casing in which a stationary vortex body and a rotatable vortex body are located so as to define a compression chamber and an expelling chamber with the stationary vortex body located between the two chambers. The stationary vortex body and the rotatable vortex body are located in the compression chamber. Each of the stationary vortex body and the rotatable vortex body has a base board and a vortex portion extends from the base board. A vortex groove is defined in an end surface of each of the vortex portion and a seal member is engaged with the vortex groove. The vortex groove includes a start end which is located close to the base board. Each of the seal members includes a cut-off portion defined in a distal end thereof and located close to the start end of the vortex groove. The cut-off portion faces an inside of the vortex groove. The refrigerant enters the gap between the cut-off portion of the seals and the grooves to push the seal members toward the vortex boards when the compressor is activated.
The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross sectional view of the compressor;
FIG. 2 is a cross sectional view along line 2—2 in FIG. 1;
FIG. 3 shows the seal member engaged with the vortex groove;
FIG. 4 shows refrigerant enters the gap between the seal member and the inside of the vortex groove;
FIG. 5 shows the base board, the vortex portion, and the seal member engaged with the vortex groove;
FIG. 6 shows a second embodiment of the seal member;
FIG. 7 shows a third embodiment of the seal member, and
FIG. 8 is a conventional seal member and the vortex groove of the vortex body.
 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 to 5, the vortex compressor of the present invention comprises a casing 1 in which a stationary vortex body 2 and a rotatable vortex body 3 are located. The rotatable vortex body 3 is rotatable relative to the stationary vortex body 2. A compression chamber 4 and an expelling chamber 5 are defined in the casing 1 and separated by the stationary vortex body 2. The stationary vortex body 2 and the rotatable vortex body 3 are located in the compression chamber 4.
Each of the stationary vortex body 2 and the rotatable vortex body 3 has a base board 21/31 and a vortex portion 22/32 extends from the base board 21/31. A vortex groove 23/33 is defined in an end surface of each of the vortex portion 22/32. A seal member 6/7 is engaged with the vortex groove 23/33.
The vortex groove 23/33 includes a start end 24/34 which is located close to the base board 21/31. Each of the seal members 6/7 includes a cut-off portion defined in a distal end 61/71 thereof which is located close to the start end 24/34 of the vortex groove 23/33. A gap 25/35 is defined between the distal end 61/71 of the seal member 6/7 and the start end 24/34 of the vortex groove 23/33 as shown in FIGS. 3 and 4 and a stepped surface 62/72 is defined in the cut-off portion and faces an inside of the vortex groove 23/33.
When the compressor is activated, the refrigerant enters into the start end 24/34 of the vortex groove 23/33 due to higher pressure and applies a force to the stepped surface 62/72, the distal end 61/71 of the seal member 6/7 is then lifted upward slightly and the refrigerant then enters the gap between the seal member 6/7 and the inside of the vortex groove 23/33 till the final end 231/331 of the vortex groove 23/33. The seal member 6/7 is pushed by the refrigerant to contact against the base board 21/31 so as to effectively seal the base board 21/31 and the vortex portion 22/32. By this way, the compression ratio can be maintained and even if the seal member 6/7 is slightly worn out, the seal member 6/7 still seals the gap by the refrigerant.
As shown in FIG. 6 which discloses a second embodiment of the seal member 6/7 wherein the cut-off portion is an inclined surface 63/73. When the compressor is activated, the refrigerant enters into the start end 24/34 of the vortex groove 23/33 due to higher pressure and applies a force to the inclined surface 63/73, the distal end 61/721 of the seal member 6/7 is then lifted upward slightly and the refrigerant then enters the gap between the seal member 6/7 and the inside of the vortex groove 23/33 till the final end 231/331 of the vortex groove 23/33. The seal member 6/7 is pushed by the refrigerant to contact against the base board 21/31 so as to effectively seal the base board 21/31 and the vortex portion 22/32.
FIG. 7 shows a third embodiment of the seal member wherein the cut-off portion is an inclined a combination surface 64/74 which is composed of an inclined section 641/741 and a vertical section 642/742. When the compressor is activated, the refrigerant enters into the start end 24/34 of the vortex groove 23/33 due to higher pressure and applies a force to the combination surface 64/74, the distal end 61/71 of the seal member 6/7 is then lifted upward slightly and the refrigerant then enters the gap between the seal member 6/7 and the inside of the vortex groove 23/33 till the final end 231/331 of the vortex groove 23/33. The seal member 6/7 is pushed by the refrigerant to contact against the base board 21/31 so as to effectively seal the base board 21/31 and the vortex portion 22/32.
While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.

Claims (2)

1. A vortex compressor comprising:
a casing;
a stationary vortex body and a rotatable vortex body located in the casing, the rotatable vortex body being rotatable relative to the stationary vortex body, a compression chamber and an expelling chamber being defined in the casing and separated by the stationary vortex body, the stationary vortex body and the rotatable vortex body being located in the compression chamber, and
the stationary vortex body and the rotatable vortex body each having a base board and a vortex portion extending from the corresponding base board, a vortex groove being defined in an end surface of each of the vortex portions of the stationary vortex body and the rotatable vortex body, a pair of seal members respectively engaged within the vortex grooves of the stationary vortex body and the rotatable vortex body, each vortex groove including a start end which is located close to the corresponding base board, each of the seal members including a cut-off portion defined in a distal end thereof and located close to the start end of the respective vortex groove, the cut-off portion facing an inside of the respective vortex groove, the cut-off portion being a combination surface which is composed of an inclined section and a vertical section.
2. The compressor as claimed in claim 1, wherein a gap is defined between the distal end of the seal member and the start end of the vortex groove.
US11/333,369 2006-01-18 2006-01-18 Seal member for vortex compressor Expired - Fee Related US7134852B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009038138A1 (en) * 2007-09-21 2009-03-26 Mitsubishi Heavy Industries, Ltd. Scroll compressor

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01121582A (en) * 1987-11-06 1989-05-15 Sanyo Electric Co Ltd Scroll type compressor
US4869658A (en) * 1987-02-27 1989-09-26 Iwata Air Compressor Manufacturing Company Limited Prevention against shifting of tip seal of scroll compressor
JPH0311101A (en) * 1989-06-09 1991-01-18 Iwata Tosouki Kogyo Kk Scroll fluid machine
JPH03246389A (en) * 1990-02-23 1991-11-01 Sanden Corp Scroll compressor
JPH06272679A (en) * 1993-03-17 1994-09-27 Tokico Ltd Scroll fluid machine
JP2002031069A (en) * 2000-07-19 2002-01-31 Keihin Corp Scroll type compressor

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4869658A (en) * 1987-02-27 1989-09-26 Iwata Air Compressor Manufacturing Company Limited Prevention against shifting of tip seal of scroll compressor
JPH01121582A (en) * 1987-11-06 1989-05-15 Sanyo Electric Co Ltd Scroll type compressor
JPH0311101A (en) * 1989-06-09 1991-01-18 Iwata Tosouki Kogyo Kk Scroll fluid machine
JPH03246389A (en) * 1990-02-23 1991-11-01 Sanden Corp Scroll compressor
JPH06272679A (en) * 1993-03-17 1994-09-27 Tokico Ltd Scroll fluid machine
JP2002031069A (en) * 2000-07-19 2002-01-31 Keihin Corp Scroll type compressor

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009038138A1 (en) * 2007-09-21 2009-03-26 Mitsubishi Heavy Industries, Ltd. Scroll compressor
JP2009074461A (en) * 2007-09-21 2009-04-09 Mitsubishi Heavy Ind Ltd Scroll compressor
EP2192304A1 (en) * 2007-09-21 2010-06-02 Mitsubishi Heavy Industries, Ltd. Scroll compressor
US20100172780A1 (en) * 2007-09-21 2010-07-08 Mitsubishi Heavy Industries, Ltd. Scroll Compressor
US8152501B2 (en) 2007-09-21 2012-04-10 Mitsubishi Heavy Industries, Ltd. Scroll compressor for preventing performance deterioration and variation due to gas leakage
EP2192304A4 (en) * 2007-09-21 2015-04-22 Mitsubishi Heavy Ind Ltd Scroll compressor

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